Horizen (ZEN)
Basics * Formerly known as ZenCash but got rebranded into Horizen in the autumn of 2018. * "A private, decentralized, and reliable platform for communications, transactions, and publishing." * No premine/ICO. Fork of ZClassic that uses the same codebase as ZCash. * Had a 51% attack on 3rd June, 2018. The attacker managed to reorganize the blockchain multiple times, successfully double spending two transactions. The losses were more than 500$ in these two double spend txs. The ZenCash network experienced a 51% attack, where one person or party controls 51% of the hash rate. The hash rate influx allowed the attacker to reorganize the blockchain several times, with the largest rollback reversing 38 blocks. The attacker also was able to double spend two massive transactions – 13,000 and 6,600 ZEN – worth more than $550,000 at current prices, according to a statement made by the development team. The attack occurred over a span of around 110 blocks, making the total attack length under four hours. According to 51Crypto, a website which estimates the theoretical cost of a 51% attack on various cryptocurrencies, it cost the attacker around $30,000. Tech * Treasury funds for development, support, marketing - 8.5% of mining reward * Halving of mining reward reduced every four years, same as Bitcoin. Miners get 88 percent of the coin distributed, while the core team keeps 8.5 percent and secure nodes have 3.2 percent. * Has Regular Full Nodes, 'Securenodes' and 'Supernodes'. # Regular Full Nodes: "Horizen wallets are full nodes, they hold the latest blockchain." # Secure nodes: "They offer enhanced privacy and powers the ecosystem of Horizen. Secure nodes make use of specific enhancement beyond what a standard blockchain node provides. You can invest in secure nodes with 42 Zen per transparent node. To run a secure node, the requirements are not that stringent. You will need to keep a 92 percent reliability score, which implies that you have to keep the node running for 92% of the time. You must also get a TLS certificate from a trusted Certificate Authority. You will also be required to maintain and propagate a full copy of the Horizen blockchain." # Super nodes: "the super nodes network introduces platform applications and sidechaining. It manages vital network and system functions like tracking and measurement of secure node uptime, multiple hosting services on side chains, and scheduling payment for node miners. You can operate a super node by investing 500 Zen. A super node operator gets to receive an equal share of 10% of block rewards if they meet acceptance on time. To run a Super node, you will need 8GB RAM memory or more, and must maintain a 96 percent reliability score, ensuring that you keep the node running for 96% of the time. You will also be required to have 100 GB of storage or more. Supernodes add two major improvements to the Horizen network. First, they allow tracking and payment of Secure Nodes to be moved on-chain, or in protocol, which is a major change from the current management which is done via external server clusters. Secondly, they provide the required infrastructure to implement Side Chaining which moves Horizen from a pure cryptocurrency to an application ready platform upon which an unbounded set of services can be built." * Horizen makes use of three main systems, the ZenChat, the ZenPub, and the ZenHide. All three systems offer users anonymous services: # ZenChat: "This feature is a secure messaging application that can work as a stand-alone product or a product embedded in a user’s wallet. With ZenChat, you can have one-on-one communication or group communication with other members of the platform. All messages shared on ZenChat are stored permanently on the blockchain technology and are encrypted with trusted algorithms such as AES-256 with Perfect Forward Secrecy (PFS); this is to avoid metaleaks. ZenChat has a 512 character limit." # ZenPub: "This is a feature that lets users anonymously publish documents, data, and media without censorship restrictions. With this feature, you can anonymously make publications using text field of the Z address, without fear of reprisal or being found out. In other words, it is a secure document publishing platform that follows open distribution protocol." # ZenHide: "This feature is what protects users and their cryptocurrency data from cryptojackers. However, Horizen uses the ZenHide feature which uses the domain fronting technique to hide the endpoint of a communication. With ZenHide, users can circumnavigate crypto-commerce blocking using domain fronting." * There are other features on the platform that are yet to be launched; they include: InstaZen (which will enable faster transaction time), ZenGrid (for rent computation), and ZenDAO. * Has ZEN sidechains. They hired IOHK to produce research and help implement. Pros & Cons Pros * Has a self funding mechanism. * Also rewards nodes. Cons * They took long to fix a zk-Snarks vulnerability Team, investors, etc. * Seem to be mostly from Italy, with the Core Devs in Milan. * Rob Viglione; leadership * Rosario Pabst; leadership * Luca Cermelli; project manager * Nerayoff, Steven; advisor * Is one of the investments chosen by Grayscale, owned by DCG (Grayscale also owns 1% of the BTC supply) Category:Coins/Tokens